Kazuya Koyama

Biography

I am a Professor of Cosmology in the Institute of Cosmology and Gravitation at the University of Portsmouth. My research interests lie in theoretical cosmology, particularly the origin of structure in our Universe and the late time acceleration of the Universe. My research is supported by the Science and Technology Facilities Council and the European Research Council’s consolidator grant “Cosmological Tests of Gravity”. I was supported by the European Research Council’s starting grant, “Modified gravity models as an alternative to dark energy” between 2008 and 2013. I was awarded my PhD from Kyoto University in 2002. Previous awards include RCUK academic fellowship, PPARC psotdoctoral fellowship, Japanese JSPS potdoctoral fellowship. In 2009 I was awarded the Philipe Leverhulme prize and in 2010 I received the Young Scientist Award of the Physical Society of Japan. I was a PI of a Royal Society International Joint Project with the Yukawa Institute at Kyoto University. The collaboration between Portsmouth and Kyoto University was awarded the Daiwa-Adrian prize in 2010.

Research interests

My main research interest lies in theoretical cosmology. I study the origin of structure in our Universe and test the early universe models using the statistical properties of the cosmic microwave background and the large scale structure of the Universe. I am also interested in explaining the late time acceleration of the Universe. Particularly I investigate a possibility to realise the late time acceleration by modifying general relativity on cosmological scales and develop cosmological tests of gravity.

Research outputs

2024

Euclid. I. Overview of the Euclid mission

Achúcarro, A., Adam, R., Adamek, J., Addison, G. E., Aghanim, N., Aguena, M., Ajani, V., Akrami, Y., Al-Bahlawan, A., Alavi, A., Albuquerque, I. S., Alestas, G., Alguero, G., Allaoui, A., Allevato, V., Alonso-Tetilla, A. V., Altieri, B., Alvarez-Candal, A., Amara, A., Avila, S., Bacon, D., Barroso, J. A. A., Beutler, F., Bose, B., Collaboration, E., Collett, T. E., Fiorini, B., Fonseca De La Bella, L., Fonseca, J., Gaztanaga, E., Joudaki, S., Koyama, K., Leclercq, F., Manera, M., Maraston, C., Markovic, K., Mellier, Y., Nadathur, S., Nichol, R. C., Noller, J., Pace, F., Pattison, C., Percival, W. J., Pollack, J. E., Pourtsidou, A., Raccanelli, A., Schewtschenko, J. A., Whalen, D. J., Winther, H. -., Youles, S.

29 Aug 2024, In: Astronomy and Astrophysics

Modeling nonlinear scales with COLA: preparing for LSST-Y1

Aguiar, B. F. d., Brando, G., Falciano, F., Gordon, J., Koyama, K., Miranda, V., Rebouças, J., Winther, H. A.

21 Aug 2024, In: Monthly Notices of the Royal Astronomical Society

A multitracer analysis for the eBOSS galaxy sample based on the effective field theory of large-scale structure

Bacon, D., Crittenden, R. G., Donald-McCann, J., Feng, Y., Gsponer, R., Koyama, K., Mu, X., Wang, Y., Zhang, W., Zhao, G., Zhao, R.

2 Jul 2024, In: Monthly Notices of the Royal Astronomical Society. 532, 1, p. 783–804

Euclid preparation. XLIV. Modelling spectroscopic clustering on mildly nonlinear scales in beyond-ΛCDM models

Aghanim, N., Amara, A., Andreon, S., Auricchio, N., Baldi, M., Bardelli, S., Bella, L. F. d. l., Bodendorf, C., Bonino, D., Bose, B., Branchini, E., Brescia, M., Brinchmann, J., Camera, S., Capobianco, V., Carbone, C., Cardone, V. F., Carella, E., Carretero, J., Carrilho, P., Casas, S., Castellano, M., Cavuoti, S., Cimatti, A., Collaboration, E., Congedo, G., Conselice, C. J., Conversi, L., Copin, Y., Costille, A., Courbin, F., Courtois, H. M., D'Amico, G., Fiorini, B., Frusciante, N., Giocoli, C., Joudaki, S., Koyama, K., Lombriser, L., Marinucci, M., Markovic, K., Moretti, C., Nadathur, S., Pace, F., Percival, W. J., Pietroni, M., Piga, L., Pourtsidou, A., Silva, A. D., Vernizzi, F.

2 Jun 2024, In: Astronomy and Astrophysics

The separate-universe approach and sudden transitions during inflation

Assadullahi, H., Gow, A. D., Jackson, J. H. P., Koyama, K., Vennin, V., Wands, D.

9 May 2024, In: Journal of Cosmology and Astroparticle Physics. 2024, 5, 35p., 053

Emulating power spectra for prereconstructed and postreconstructed galaxy samples

Feng, Y., Gil-Marín, H., Guo, H., Koyama, K., Li, Y., Nishimichi, T., Percival, W. J., Wang, Y., Wu, Y., Zhai, Z., Zhang, H., Zhao, G. B., Zhao, R.

1 May 2024, In: Astrophysical Journal. 966, 1, 15p., 35

Cosmological constraints on early dark energy from the full shape analysis of eBOSS DR16

Bacon, D., Crittenden, R., Donald-McCann, J., Gsponer, R., Koyama, K., Mueller, E., Simon, T., Zhao, R.

1 May 2024, In: Monthly Notices of the Royal Astronomical Society. 530, 3, p. 3075–3099

Extracting high-order cosmological information in galaxy surveys with power spectra

Ge, F., Gil-Marín, H., Hahn, C., Hikage, C., Koyama, K., Mu, X., Percival, W. J., Takahashi, R., Wang, Y., Yu, Y., Zhang, W., Zhao, G., Zhao, R., Zhu, H.

18 Apr 2024, In: Communications Physics. 7, 9p., 130

Emulating power spectra for pre- and post-reconstructed galaxy samples

Feng, Y., Gil-Marín, H., Guo, H., Koyama, K., Li, Y., Nishimichi, T., Percival, W. J., Wang, Y., Wu, Y., Zhai, Z., Zhang, H., Zhao, G., Zhao, R.

24 Feb 2024, In: The Astrophysical Journal

2023

Fast production of cosmological emulators in modified gravity: the matter power spectrum

Baker, T., Fiorini, B., Koyama, K.

22 Dec 2023, In: Journal of Cosmology and Astroparticle Physics. 2023, 12, 26p., 045

Analysis of unified galaxy power spectrum multipole measurements

Beutler, F., Donald-McCann, J., Gsponer, R., Koyama, K., Zhao, R.

1 Dec 2023, In: Monthly Notices of the Royal Astronomical Society. 526, 3, p. 3461–3481

Cosmology with the Laser Interferometer Space Antenna

Annis, J., Ares, F. R., Auclair, P., Avelino, P. P., Avgoustidis, A., Bacon, D., Baker, T., Barausse, E., Barreiro, T., Bartolo, N., Belgacem, E., Bellomo, N., Ben-Dayan, I., Bertacca, D., Besancon, M., Blanco-Pillado, J. J., Blas, D., Boileau, G., Bonilla, A., Bonvin, C., Bosso, P., Calabrese, M., Calcagni, G., Caldwell, R., Caprini, C., Carbone, C., Cembranos, J. A. R., Chala, M., Chang, C., Chen, H., Chernoff, D., Christensen, N., Clesse, S., Clough, K., Comelli, D., Congedo, G., Contaldi, C., Crisostomi, M., Criswell, A., Croon, D., Cui, Y., Cusin, G., Cutting, D., Dalang, C., Das, S., Dayal, P., Desjacques, V., Dimastrogiovanni, E., Domcke, V., Dorsch, G. C., Durrer, R., Easther, R., Escoffier, S., Ezquiaga, J. M., Fasiello, M., Ferrans, S., Figueroa, D. G., Flauger, R., Franciolini, G., Frusciante, N., Fryer, C., Fumagalli, J., Gair, J., Garcia-Bellido, J., Gordon, C., Gould, O., Hendry, M., Hindmarsh, M., Holz, D., Hooper, D. C., Iacconi, L., Jain, R. K., Jenkins, A. C., Jinno, R., Joana, C., Kajfasz, E., Karnesis, N., Konstandin, T., Kopp, J., Koushiappas, S. M., Koyama, K., Kozaczuk, J., Kumar, U., Kunz, M., Kuroyanagi, S., Laghi, D., Lagos, M., Lewicki, M., Lilley, M., Lizarraga, J., Lobo, F. S. N., Lombriser, L., Luca, V. D., Madge, E., Maggiore, M., Maleknejad, A., Malhotra, A., Mancarella, M., Mandic, V., Mangiagli, A., Martins, C. J. A. P., Matarrese, S., Mazumdar, A., Meerburg, P. D., Meyer, R., Mimoso, J. P., Morales, E. R., Mukherjee, S., Musco, I., Nardini, G., Nesseris, S., No, J. M., Nunes, N., Oikonomou, V., Orlando, G., Pacucci, F., Palmese, A., Papanikolaou, T., Peloso, M., Petiteau, A., Pieroni, M., Pilo, L., Pinol, L., Pol, A. R., Pozzo, W. D., Pratten, G., Prokopec, T., Quenby, J., Raccanelli, A., Rastgoo, S., Renaux-Petel, S., Renzini, A. I., Ricciardone, A., Riotto, A., Roest, D., Rollo, R., Romano, J. D., Rummukainen, K., Sakellariadou, M., Saltas, I. D., Scalisi, M., Schimd, C., Schmitz, K., Schwaller, P., Secroun, A., Sergijenko, O., Servant, G., Silva, A. d., Simakachorn, P., Sopuerta, C. F., Sorbo, L., Sousa, L., Speri, L., Steer, D. A., Tamanini, N., Tasinato, G., Tereno, I., Tolley, A., Torrado, J., Unal, C., Urrestilla, J., Vagenas, E. C., Vennin, V., Vernieri, D., Vernizzi, F., Vis, J. v. d., Volonteri, M., Wachter, J. M., Wands, D., Wardell, B., Weir, D. J., Weygaert, R. v. d., Witkowski, L. T., Zhdanov, V. I., Zumalacárregui, M., Zwart, S. P., Çalışkan, M., Özsoy, O., Świeżewska, B.

23 Aug 2023, In: Living Reviews in Relativity. 26, 5, 254p., 5

Revisiting Vainshtein screening for fast N-body simulations

Brando, G., Koyama, K., Winther, H. A.

20 Jun 2023, In: Journal of Cosmology and Astroparticle Physics. 2023, 06, 38p., 045

Euclid: Modelling massive neutrinos in cosmology -- a code comparison

Adamek, J., Aghanim, N., Amendola, L., Angulo, R. E., Arnold, C., Auricchio, N., Baldi, M., Biagetti, M., Bonino, D., Bose, B., Branchini, E., Brescia, M., Camera, S., Capobianco, V., Carbone, C., Cardone, V. F., Carretero, J., Castander, F. J., Castellano, M., Castro, T., Cavuoti, S., Cimatti, A., Dakin, J., Dolag, K., Elbers, W., Fidler, C., Giocoli, C., Hannestad, S., Hassani, F., Hernández-Aguayo, C., Koyama, K., Li, B., Mauland, R., Monaco, P., Moretti, C., Mota, D. F., Parimbelli, G., Partmann, C., Percival, W. J., Potter, D., Schneider, A., Schulz, S., Springel, V., Stadel, J., Tram, T., Viel, M., Villaescusa-Navarro, F., Winther, H. A., Wright, B. S., Zennaro, M.

16 Jun 2023, In: Journal of Cosmology and Astroparticle Physics. 2023, 06, 50p., 035

Non-perturbative non-Gaussianity and primordial black holes

Assadullahi, H., Gow, A. D., Jackson, J. H. P., Koyama, K., Vennin, V., Wands, D.

30 May 2023, In: Europhysics Letters. 142, 4, 7p., 49001

View all my research outputs

Professor Kazuya Koyama

Biography

Research interests

Research outputs

2024

2023